Pedestrians cover their face as they walk along the dusty road in Kathmandu, Nepal February 27, 2017. Nepal has forced 2,500 old vehicles off roads in its capital city of Kathmandu, part of a fight against alarming air pollution levels that have hit nine times World Health Organisation (WHO) limits. Air pollution has been a chronic problem in rapidly growing Kathmandu, which sits in a Himalayan valley and is home to more than 3mn people. (Photo by Navesh Chitrakar/Reuters)

A Palestinian father evacuates his wounded daughter from the rubble of a destroyed house after an Israeli air strike in Gaza City, 16 May 2021. A total of 174 people have been killed in Israeli raids on Gaza, including 47 children and 29 women, the Palestinian Ministry of Health said on Sunday. In response violent confrontations between Israeli security forces and Palestinians in Jerusalem, various Palestinian militant factions in Gaza launched rocket attacks on Israel since 10 May, resulting in retaliatory strikes by Israel on Gaza. (Photo by Haitham Imad/EPA/EFE)

Palestinians inspect a destroyed street after an Israeli strike in Gaza City, 13 May 2021. In response to days of violent confrontations between Israeli security forces and Palestinians in Jerusalem, various Palestinian militants factions in Gaza launched rocket attacks since 10 May that killed at least six Israelis to date. Gaza Strip's health ministry said that at least 65 Palestinians, including 13 children, were killed in the recent retaliatory Israeli airstrikes. Hamas confirmed the death of Bassem Issa, its Gaza City commander, during an airstrike. (Photo by Mohammed Saber/EPA/EFE)

A woman wears a mask while carrying a dog in the street on January 22, 2020 in Wuhan, Hubei province, China. A new infectious coronavirus known as “2019-nCoV” was discovered in Wuhan as the number of cases rose to over 400 in mainland China. Health officials stepped up efforts to contain the spread of the pneumonia-like disease which medicals experts confirmed can be passed from human to human. The death toll has reached 17 people as the Wuhan government issued regulations today that residents must wear masks in public places. Cases have been reported in other countries including the United States, Thailand, Japan, Taiwan, and South Korea. (Photo by Getty Images/China Stringer Network)

Palestinian groom Mohamed abu Daga and his bride Israa wear face masks amid the COVID-19 epidemic, during a photoshoot at a studio before their wedding ceremony in Khan Yunis in the southern Gaza Strip, on March 23, 2020. Authorities in Gaza confirmed on March 22 the first two cases of novel coronavirus, identifying them as Palestinians who had travelled to Pakistan and were being held in quarantine since their return, as the United Nations warned of potential disastrous outcomes to an outbreak given the high poverty rates and weak health system in the coastal strip, under Israeli blockade since 2007. (Photo by Said Khatib/AFP Photo)

A government employee reacts as she is sprayed with disinfectant before entering a government office building to curb the spread of COVID-19 on March 19, 2020 in Pasig city, Metro Manila, Philippines. The Philippine government has sealed off Luzon, the country's largest and most populous island, to prevent the spread of COVID-19. Land, sea, and air travel has been suspended, while government work, schools, businesses, and public transportation have been ordered shut in a bid to keep some 55 million people at home. The Philippines' Department of Health has so far confirmed 217 cases of the new coronavirus in the country, with at least 17 recorded fatalities. (Photo by Ezra Acayan/Getty Images)

A woman taking a nap on mangoes at city market area after the city eased the lockdown in Bangalore, India 12 July 2021. The Karnataka government eases in covid-19 related lockdown restrictions in the wake of lower coronavirus cases and positivity rate falling below 5% percent. The Karnataka state government administering record 2.5-crore doses till date since the vaccination drive was launched across the state on January 16, Karnataka ranked first in South India in inoculating maximum number of its eligible population, said state Health Minister K. Sudhakar. (Photo by Jagadeesh N.V./EPA/EFE)

A health worker shows an empty syringe after inoculating a woman with AstraZeneca's COVID-19 vaccine during the first day of a nationwide three-day vaccination drive at a school in Quezon city, Philippines on Monday, November 29, 2021. There has been no reported infection so far caused by the new variant in the Philippines, a Southeast Asian pandemic hotspot where COVID-19 cases have considerably dropped to below 1,000 each day in recent days, but the emergence of the Omicron variant has set off a new alarm. (Photo by Aaron Favila/AP Photo)